Monday, October 24, 2011

Today, we started class by receiving a sheet on some new requirements for our blogs. They are that each blog you do must have at least one picture, and you must comment of other peoples' blogs st least 3 times before each person has finished the 2nd round, but cant do more that 2 comments a week. These comments could include constructive criticism as long as actually productive, and comments like "blah blah blah... was really good" are not allowed and aren't useful, so you should think before posting a comment. After that, we finished our notes on what makes us sick, but because the pages were mixed up we sort of had to skip around. We did pages (not in the correct order by the way) 22, 24, 1st half of 25 but other half was a review of T and B cells, 26, 27, 28, and 29. these pages were focused on the T and B cells, and how they worked. T cells have 3 types, cytotoxic (killer) T cells, helper T cells, and a third type (found in the study section on pages 49-55 which you should read) called Suppressor T cells. Helper T cells identify the foreign substance in the body, mark it to be destroyed, and stimulates the growth of cytotoxic T cells and B cells. Cytotoxic T cells kills infected body cells that are malfunctioning or are producing pathogens. Suppressor T cells slows activity of T and B cells after the infection is dealt with. B cells produce memory cells and plasma cells. Plasma cells create antibodies to combat the infection and memory cells keeps formula of cells that combat a certain infection or disease. We also learned about primary and secondary immune responses. The primary immune response occurs when a new or mutated pathogen enters the body, and it takes a few days to produce antibodies, but the memory cells store formula to combat re-infection. Secondary immune response occurs with the pathogens 2nd infection, and it killed off much more rapidly because of the memory cells, and is often symptom free.

Immune disorders were in our notes as well. they are the consequence of a malfunction of the immune system. They include allergies, autoimmune disorders - system turns against bodies own molecules, and immunodeficiency diseases - when body lacks one of more parts of the immune system. Some types of autoimmune diseases are rheumatoid arthritis, juvenile diabetes, multiple sclerosis, and lupus. Some immunodeficiency diseases are SCID (Severe Combined Immunodeficiency) which there is few T and B cells, Hodgkin disease, and AIDS/HIV, which attacks helper T cells. After that we watched a few short movies on T and B cells/antibodies. Antibodies attach to pathogens, stopping them from infecting cells (neutralization), then preform agglutination, or clumping so a phagocyte can kill them in phagocytosis. B cells make humoral immunity, in which B cells send out antibodies, each which can only bind to one type of antigen and make memory cells and plasma cells. Helper T cells sends signals to stimulate growth of other T and B cells after marking infected cell.

Variable portion= there are two variable portions to each antibody so they can latch on to two different invading microbes. If enough accumulate and "clump" together (agglutination), the microbes cannot function.

Thursday, October 20, 2011

Today in class, we completed page 33 in the UP, pages 12-15 in the notes, and finised the bacteria lab.

Page 33: Analyse the diagram provided in the UP and answer the subsequent questions. Correct answers to the questions posted below.

1. Which of the antibiotics would you use to prevent the growth of B. subtilis?

Neomycin is the best antibiotic for inhibiting B. subtilis growth. Aureomycin and erythromycin also work.

2. Which of the antibiotics would you use to prevent the growth of E. coli?

Tetracycline is the best antibiotic for inhibiting E. coli growth. Aureomycin also works.

3. Are both organisms equally sensitive to antibiotics? Explain.

No. More antibiotics inhibit one organism, with greater effect, than the other.

4. Which of the two organisms are more sensitive to antibiotics in general?

B. Subtilis

5. If you wanted to inhibit both organisms with one antibiotic, which would you use?

Aureomycin

6. If E. coli is beneficial and B. subtilis is harmful and you were infected with both, which antibiotic would you use?

Neomycin would inhibit the growth of both bacteria best. Erythromycin would also work.

7. In general, what can you conclude about bacteria and antibiotics from this experiment?

Antibiotics are not as specific as enzymes, and may inhibit the growth of multiple strains of bacteria. Different bacteria are sensitive to different antibiotics with different degrees of sensitivity.

8. What features does this experiment lack that it should have?

A control group

9. How would you correct this omission?

Add a paper disk.

Notes:

Bacteria Lab:

Surface Lab:

1. Find your petri dish. DO NOT open it! Possibly dangerous bacteria could be growing in it.

2. Observe the petri dish. You should see bacteria colonies (they look like little circular clumps). Count the number of colonies present on the surface of the agar. Do not confuse bacteria colonies with fungus, which also may have grown. Fungus will have little "arms." Don't count it!

3. Record the number of colonie in each quadrant.

4. Safely dispose of the petri dish.

Antibiotic lab:

1. Find your petri dish and a metric ruler.

2. Find the zones of inhibition around each antibiotic, if any. They should look like clear, bacteria free circular "halos' around the antibiotic disk.

3. Measure the diameter of each zone of inhibition in millimeters. If the circle of the zone of inhibition is not complete or fully measurable, measure the radius and multiply it by two.

4. Record the diameter of each zone of inhibition for each antibiotic.

5. Safely dispose of the petri dish.

Results of these labs varied between groups. If you were absent today and unable to recive results from your group, here is a sample of some of the results collected today:

Surface Lab:

Control: 12 colonies

Doorknob: 145 colonies

Faucet Handle: 78 colonies

Desk: 178 colonies

Antibiotic Lab:

Control: 0 mm

Streptomycin: 24 mm

Penicillin: 13 mm

Neomycin: 15 mm

Homework: Continue working on reasearch/ scripts for disease project, finish pp. 31-32 in UP for tomorrow, and begin spice lab (pp. 37-41 in UP)

Wednesday, October 19, 2011

Today, we set up our Bacteria Labs in class so that they would ready for us to observe the following day. We split up into groups of two. One of the partners set up "How common are bacteria and how quickly do they reproduce"

They needed to follow the directions on pg 19-20 in UP to do this which included

labeling their dish into 4 separate areas

then using 3 different items to wipe on top of the different areas, one in each, with no object wiped in the fourth section as that is the control

make sure to label which items were wiped in each section

close your petri dish now and give it to your teacher

The other partner followed the procedure on pages 23-24 for Lab "Using Antibiotics to stop bacterial growth"

follow these steps:

label your dish into 4 separate areas

take a cotton swab, dip it in bacteria broth, and then wipe it all of the the petri dish nutrient agar so that each section has the same amount

take three different antibiotics, using the tweezers, and place them in separate sections

take a plain piece of paper and put it in the fourth section as your control

make sure you label which antibiotic is in each section

close your petri dish now and give it to your teacher

We also took an extensive amount of notes, all of which can be found through the Gbs Moodle page if you go to the Bio Metacourse and click on notes for UNIT 3. For an odd reason, my link is not working however so I hope that I am just unlucky and that you will all have no trouble with the link loading. The pages we covered in the notes packet were 1-12.

Monday, October 17, 2011

AGENDA-Today in class we finished what was left of the Flu video from October 13th. The last part of the video basically summarized how Holly Jones was recovering from her influenza virus with antibodies, etc.

"Travel inside the body of Holly Jones, a 25-year-old motorcycle courier who becomes a victim in the cellular war between her immune system and the influenza virus."

After we finished the last part of the previous video, we started a new film "Understanding Viruses" (part 1 and most of part 2), along with the questions on page 15 of the Unit Packet. During the film, we were to answer the questions, turning in p.15 of UP at the end of class.

The video briefly talked about an important virologist, Jonas Salk. He was famous for creating an effective Polio Vaccine.

We also went over the Mitosis notes from last night's homework.-To find the notes log onto moodle and go to the biology page, then scroll down to Unit 2- Cells R us and click on the folder called class notes unit 2 and then click CH 7mitosis notes

In class we started the Mitosis lab in the UP packet on pages 53-56. We will finish the lab later in class.

Wednesday, October 5, 2011

In class today we first checked our Egg Mitosis DEMO. The egg was soaked in vinegar and we had to draw a picture and describe it. The shell was being eaten away by the vinegar so it did not make a noise when it was touched. It was soft instead of hard. There were bubbles all over it because the shell was being eaten away and there was no color change.

Next in class we did a lab about osmosis and diffusion on pages 41-42. Under a microscope, we looked at elodea leaves with regular tap water and 6% salt water. The plant cells looked normal in the tap water. The chloroplasts were all on the outside of the cell, the cell membrane was close to the wall, the vacuole was visible and the nucleus was seen. In the 6% salt water, though, the cell membrane condensed and the vacuole shrunk. Here is a cartoon showing what happened from http://waynesword.palomar.edu/images/elcell7a.jpg:

As can be seen, the water left the vacuole and it could not be seen, but is still present.

We also drew a picture (similar to these pictures) of what we saw in each type pf water. We also labeled what we saw. We then answered questions from the lab on page 42 by ourselves, and then went over them in class together.

We filled out page 43, which was about osmosis and different water concentrations inside and outside of cells.

Today we had a quiz in everything we've learned so far in the cells unit. We read over and completed day 1 of the Egg Osmosis DEMO in class. Also we did the "Diffusion Through a Cell Membrane" lab. Due today was to read pages 37-39 in UP.

The Egg Osmosis DEMO

The Egg Osmosis Demo, found on pages 45-47 in the unit packet, talks about hows osmosis is the diffusion of water across a semi-permeable membrane. It also talks about homeostasis and how it is maintained in part by controlling the movement of materials into and out of the cell.

In class Mrs. Andrews held up an egg and we drew a picture of it and made observations like; white, hard shell, and oblong. This was recorded under day 1-raw egg on page 46 in the unit packet.

Diffusion Through a Cell Membrane Lab

1. We drew a diagram of what our materials will look like when they are set up. There is the dialysis tubing that

contains glucose, starch, and water that is placed in a beaker which contains 50mL of water and iodine (brownish yellow color).

2. We proceeded with the lab by adding glucose and starch to the tubing and tying it off then placing it in a beaker filled with iodine and water for 15 minutes.

3. After 15 minutes we came back and the starch in the tubing had turned a blue black color and settled to the bottom. Also the iodine diffused in the tubing because the liquid inside the tubing was a brownish yellow color.

4. By dipping a piece of Tes-Tape (glucose indicator paper) into the liquid in the beaker we found that there was a

presence of glucose outside the tubing because the tape turned a to light green. From this we

concluded that the glucose diffused from inside the dialysis tubing to the beaker.

After 15 minutes the beaker looked like this. With the starch dyed blue/black because of the iodine and iodine diffused into the tubing as well as the glucose diffused into the beaker although you cannot see it.

From these results we concluded that:

1. The iodine diffused from the high concentration in the beaker to the low concentration in the dialysis tubing.

2. The glucose diffused from the high concentration in the tubing to the low concentration on the beaker.

3. The water did a little bit of diffusing both into the tubing and out.

4. Starch molecules are a lot larger than glucose, water, and iodine molecules because they couldn't diffuse through the dialysis tubing membrane.

Tuesday, October 4, 2011

Today we finished the notes on the cytoskeleton and began notes on the cell membrane. There is a quiz tomorrow on everything we've learned so far in the section. There is also a lab tomorrow. The homework is to read pages 37-39 in our UP and draw a picture of the lab.

Sunday, October 2, 2011

At the beginning of class on Friday, we turned in both of our labs that we had finished. After turning in our labs we immediately began taking notes in our Basics of Organic Chemistry notes packet (yellow packet). It was a rushed day because of the shortened periods but we managed to finish taking notes from the "CELLS Structure and Functions" part of our notes to most of the "Plasma Membrane" section of our notes.

1. Sections of our notes that we recognized as important were

"World of Cells Theory"

"Membrane Structure"

2. Bullet points in our notes packet we underlined :

Scanning Electron Microscope- detailed architecture of the surface of a cellTransmission Electron Microscope- exploring the internal structure of acell

Nuclear Envelope: double membrane with pores that surrounds the nucleus

DNA attached to protein is found in the nucleus in the form of chromatin

Ribosomes are responsible for assisting in protein synthesis by makingenzymes and proteins for the organism

In the Endomembrane Review we circled Rough ER, Golgi apparatus,Vacuole, Lysosome, and Plasma membrane because they all worktogether

Stroma- thick fluid inside the inner membrane (of chloroplasts)

3.Ideas discussed to help us comprehend what we learned better:

Ribosomes go from the nucleus to the Rough Endoplasmic Reticulum (Rough ER) because it transports the ribosomes to where they need to go.

In diagrams, proteins will always be purple

The Golgi Apparatus is like a UPS system because it finishes, stores, and distributes chemical products of the cell.

Lysosomes are like garbage centers.

In diagrams, Grana (located in chloroplasts) looks like stacks of pancakes.

When you hear ATP, think 'energy'.

4. Concepts/ideas we should be sure to review

shapes and organelles unique to bacteria

different parts of plant and animal cells

being able to tell the difference between smooth ER and the golgi apparatus

Today in Biology the class participated in a cell structure and function lab. This lab included a microscope to observe the cells. The cells came from different substances and objects such as tomato skin, potato skin, frog blood, streptococcus lactis, onions, algae, elodea leaves and the inside of human cheeks. The cells were observed in a slide. Substances such as iodine, water and methylene were put on the slide as well to help make the cells visible. The lab did not include a true experiment involving control and independent variables but was more of observations and the study of cells. The lab was divided into two different parts; part two was considerably longer with the observation of six different cells. There was also a prelab and homework.

Prelab (pgs. 23-26)

Before students could participate in the lab they had to complete a prelab that was divided into two different parts. Part one dealt with prokaryotic cells and their organelles/structures. There was a picture of a prokaryotic and five different structures students had to label and describe their functions. On the second page of part one there was two pictures of eukaryotic cells; one was of a plant cell, the other,an animal cell. Once again the students had to label eighteen different structures and describe their functions. Part two was the comparison of plant and animal cells. There was a chart that had to be filled out with organelles that were unique in only one of the cell types, plant or animal. This was followed by pre lab questions that dealt with previewing the lab and answering questions about the materials and connecting them to the previous activity.

Part I (pg. 27-28)

Part one of the lab dealt with the observation of the prokaryotic cells from streptococcus lactis and eukaryotic cells from the skin of an onion. The streptococcus lactic was put on a slide with a cover slip and observed under 400x power of a microscope. The students than had to draw what they observed. The students than had to peel off the transparent membrane of an onion and place it on a slide with one drop of iodine and a cover slip. Once the slide was prepared the slide was observed under the microscope at 400x power. Once again what was seen under the microscope was drawn out on the designated area in the packet.

Part II (pgs. 28-30)

Part two of the lab was the observation of eukaryotic cells, both plant and animal. Students had to first pull off an elodea leaf with tweezers and place it on a wet mount slide with a cover slip. This leaf was than observed under the microscope at low power and high power. The observations were than drawn on the packet, the students could choose whether to draw the image at low power or the 400x power (high). The elodea leaf was than observed in a slide that now had iodine. The iodine stain maid the organelles more visible. The students than had to sketch what the elodea leaf looked like under high power. The students than had to take a toothpick and rub the inside of their cheek and mix the cells on the toothpick on to a wet mount slide with methylene blue stain. After placing a cover slip over the slip the slide was to be placed under the microscope and the cells observed under low than high power. The students than had to sketch their observations of the cheek cell under high power and label the parts of the cheek cell. The next substance to be observed was frog blood. Students had to take a pre prepared slide of frog blood. The students must than title the magnification they chose to observe the frog blood cells under. The students than had to cut off a piece of potato skin and place it on a wet mount slide with a cover slip. The potato skin was than observed under the microscope power of choosing and the observations sketched out on the designated area on the packet. The students than had to cut off a piece of tomato skin and place it on a wet mount slide with a cover slip. The slide was than to be placed under the microscope and observed under the power of choosing, the observations were than to be sketched in the packet. The last substance to be observed was a piece of algae. The algae was placed on a wet mount slide and observed under the microscope and the observations were sketched out.

Post lab/ homework (pgs. 31-32)

The homework for this lab was to answer analysis questions on pg. 31 and to label the parts of the cell pictures on pg. 32. Also to finish up any unfinished questions on pgs. 27-30.